Antimicrobial material for implanting in bones

Abstract

The invention relates to an antimicrobial material for implanting in bones and for coating or producing an implant or an implantable medical device, whereby particles formed from an antimicrobial material are remotely dispersed inside a matrix material that forms a matrix when hardened. In order to improve the compatibility of the antimicrobial material, the invention provides that the metal is formed from aggregates of primary particles having an average particle size ranging from 10 to 100 nm.

1. An antimicrobial implant material for implanting in bones, the material comprising:
 aggregates formed from an anti-microbial metal; and 
 a polymer matrix material which forms a matrix in the cured state, 
 wherein the aggregates are discrete and finely dispersed in said matrix material, wherein the aggregates are highly porous and are formed of primary particles connected together by necks, wherein the primary particles have an average particle size between 10 and 100 nm, and wherein the metal is not more than 5.0% by weight based on the weight of the polymer matrix material. 
 
     
     
       2. The antimicrobial material of  claim 1 , wherein the aggregates have an average aggregate size of from 1 to 20 μm. 
     
     
       3. The antimicrobial material of  claim 2 , wherein the aggregates have an average aggregate size of 10 to 20 μm. 
     
     
       4. The antimicrobial material of  claim 1 , wherein the aggregates have a surface area of from 3 to 6 m 2  per gram. 
     
     
       5. The antimicrobial material of  claim 1 , wherein the aggregates have a porosity of up to 95%. 
     
     
       6. The antimicrobial material of  claim 1 , wherein the aggregates are produced by inert gas vaporization and condensation. 
     
     
       7. The antimicrobial material of  claim 6 , wherein the aggregates are produced under a pressure of from 10 to 100 mbar of inert gas. 
     
     
       8. The antimicrobial material of  claim 1 , wherein the metal is formed from one or more of the following components: Ag, Au, Pt, Pd, Ir, Sn, Cu, Sb, Zn. 
     
     
       9. The antimicrobial material of  claim 1 , wherein the metal has an essentially undisordered lattice structure. 
     
     
       10. The antimicrobial material of  claim 1 , wherein the metal content is not more than 2.0% by weight based on the weight of the polymer matrix material. 
     
     
       11. The antimicrobial material of  claim 10 , wherein the metal content is 0.01 to 2.0% by weight, based on the weight of the polymer matrix material. 
     
     
       12. The antimicrobial material of  claim 1 , wherein the aggregates are completely infiltrated with the polymer matrix material. 
     
     
       13. The antimicrobial material of  claim 1 , wherein the polymer matrix material is formed from a plurality of components. 
     
     
       14. The antimicrobial material of  claim 1 , wherein the polymer matrix material comprises acylic esters and/or methacrylic esters. 
     
     
       15. The antimicrobial material of  claim 1 , wherein the aggregates are homogeneously dispersed in the polymer matrix material. 
     
     
       16. An implant or implantable medical device formed from, or at least partially coated with, the antimicrobial implant material of  claim 1 . 
     
     
       17. A process for producing the antimicrobial material of  claim 1 , comprising the steps of:
 a) vaporizing and condensing the metal under an inert gas atmosphere, wherein the pressure of the inert gas and the vaporization temperature are adjusted so that discrete aggregates consisting of primary particles having an average particle size of from 10 to 100 nm are formed, and 
 b) mixing the aggregates with a curable polymer matrix material. 
 
     
     
       18. The process of  claim 17 , wherein the aggregates are size classified after step (a). 
     
     
       19. The process of  claim 17 , wherein the aggregates are sized classified to have an average aggregate size in the range of from 1 to 20 μm. 
     
     
       20. The process of  claim 17 , wherein the aggregates are size classified to have an average aggregate size in the range of 10 to 20 μm. 
     
     
       21. The process of  claim 19 , wherein the polymer matrix material is in the liquid state. 
     
     
       22. The process of  claim 17 , wherein the inert gas comprises at least one of the following gases: argon, krypton, xenon, helium. 
     
     
       23. The process of  claim 17 , wherein the aggregates have a surface area of from 3 to 6 m 2  per gram. 
     
     
       24. The process of  claim 17 , wherein the aggregates have a porosity of up to 95%. 
     
     
       25. The process of  claim 17 , wherein the metal is formed from one or more of the following constituents: Ag, Au, Pt, Pd, Ir, Sn, Cu, Sb, Zn. 
     
     
       26. The process of  claim 17 , wherein the metal has an essentially undisordered lattice structure. 
     
     
       27. The process of  claim 17 , wherein the matrix comprises not more than 2.0% of metal based on the weight of the polymer matrix material. 
     
     
       28. The process of  claim 27 , wherein the matrix comprises 0.01 to 2.0% of metal based on the weight of the polymer matrix material. 
     
     
       29. The process of  claim 17 , wherein the aggregates are completely infiltrated with the polymer matrix material. 
     
     
       30. The process of  claim 17 , wherein the polymer matrix material is formed from two component. 
     
     
       31. The process of  claim 17 , wherein the polymer matrix material comprises acylic esters and/or methacrylic esters. 
     
     
       32. The process of  claim 17 , wherein the aggregates are homogeneously dispersed in the polymer matrix material. 
     
     
       33. The process of  claim 30 , wherein the aggregates are initially admixed with one of the two polymer components. 
     
     
       34. An antimicrobial implant material for coating or producing an implant or an implantable medical device, comprising discrete aggregates formed from anti-microbial metal dispersed in a polymer matrix material which forms a matrix in the cured state, wherein the aggregates are highly porous aggregates formed of primary particles connected together by necks, wherein the primary particles have an average particle size between 10 and 100 nm, and wherein the metal content is not more than 5.0% by weight based on the weight of the polymer matrix material.